Journal of thermal analysis

, Volume 46, Issue 2, pp 337–345 | Cite as

High pressure studies on new chiral compounds exhibiting TGBA phase

  • A. Daoudi
  • A. Anakkar
  • J. -M. Buisine
  • F. Bougrioua
  • N. Isaert
  • H. T. Nguyen
13th IUPAC Conference on Chemical Thermodynamics


Effects of high pressures on phase sequences of the two homologousn=16 andn=18 of the (3-fluoro-4 ((R) or (S)-methylheptyloxy) 4, (4″-fluoro benzoyloxy) tolans) series have been studied. Both compounds exhibit the new twisted Smectic A phase called Twist Grain Boundary TGBA phase. The high pressure experiments were performed by thermobarometric analysis. The order of the transitions (first or second) have been determined in respect to pressure and temperature. The pressure-temperature phase diagrams show that the TGBA phase is stabilized by increasing pressure; an inducedN* phase appears under high pressure for n=18 leading to the observation of TGBA-N*-I triple point.


thermobarometric analysis Twist Grain Boundary phase 


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Copyright information

© Akadémiai Kiadó 1996

Authors and Affiliations

  • A. Daoudi
    • 1
    • 3
  • A. Anakkar
    • 1
    • 2
  • J. -M. Buisine
    • 1
    • 3
  • F. Bougrioua
    • 1
    • 2
  • N. Isaert
    • 1
    • 2
  • H. T. Nguyen
    • 4
  1. 1.Laboratoire de Dynamique et Structure des Matériaux MoléculairesU.R.A. CNRS n∘801France
  2. 2.Equipe de Physique des Stases AnisotropesUniversité de Lille 1Villeneuve d'Ascq Cédex
  3. 3.Equipe de Thermophysique de la Matière CondenséeUniversité du LittoralDunkerque
  4. 4.Centre de Recherche Paul PascalChâteau BrivazacPessacFrance

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